Mounting for hand grinding devices



y 1933- SCHULTE 1,917,906

MOUNTING FOR HAND GRINDING DEVICES Filed Aug. 29, 1930 /Nl/E/V 70/? [00/5 5010A 75 ATTORNEYS Patented July 11, 1933 I LOUIS SGHULTE, OF

* lenses COMPANY, A CORPORATION" or rE'NNsYLvANIA MOUNTING FOR HAND enrNiiiNe nnvrons Applicationjfiled August 29,1930, -ser1a.1No.47e,c4o.

This invention relates to apparatus used in the art of grinding orsurfacing of sheets or stripsof material especially of the thinner gauges, and is particularly adapted for removing deep pit, tool or other marks in steel or other metal to be ground or polished.

These marks are usuallyremove'd by hand grinding before the entire sheet or strip is subjected to its final grinding or'polishing operation; I Heretofore great difficulty has been experienced in removing these deeperfmarks from sheets, strips and othermaterial and getting an even and smooth surface.

Heretofore it has also been difficult to feed acgrinding wheelin prevent the formation of grinder marks across the grain which constitute additional defects and are removed only with great difi- -culty. W q i This hand grinding has usually been done by ,a rather heavy portable grinder which had to be lifted by the operator. The general obj 'ect of my invention is theref0re,'to produce a grinding device which will be especially adapted to remove pits, tool marks and other objectionable surface defects from sheets, strips, or other flat. surfaces.

Another object of this duce a grinding device which can be supported while the deviceisgrinding whereby theoperator is relieved of the necessity oflifting a heavy weight while grinding and whereby he is enabled to control the grinding operation in a very sensitive manner.

Another obj ect of this invention is 'to proto rest on the sheet ormaterial being ground 1 which will not mark, indent or deface the i finished surface of the material. 1 g 7 Another object of thisinvention is to provide a rolling support for a hand'grindingdevice which will tend to roll the grinding unit parallel to the plane of rotation of the grinding wheel. Another object of this invention is to provide a support for a hand grinding unit which will permit thelateral movement of the entire grinding unit, andwhich will permit the tilting of the unit and a straight lineiso as to ,inventionsis to pro- BnAcKENnrneE, PnNNsYLvA rA, AssIeNon r0 :ALLE-eirnNYsrE-nn whichwin permit therotation'of the entire unitabout its axis; 7 I g Another object of thisinverition isto produce an antifriction mounting for a carrying Wheel for a grinding device which will be simple and durable in construction. N

Another object of thisinvention is to produce ac'arrying wheel which will be soft and resilient and which will prevent slippage of.

the grinding unit n smooth, polished surfaces being treated. H v

- Another ob 'ect 0 diameter as the grinding wheel; and which will permit the grinding operation to be performedwith the axis ofth'e grinding wheel Parallel to'the plane Ofljhegupface beinggro l; V

- ,Another ob ect ofthis invention istopro- "'This---invent1on also consists in pertain "other'features of construction and in the'comblnatlon'f and arrangement of the several i use w n is to p e- 1 duce carrying wheel for a hand grinder unit which will bev of substantiallythe same permeate hereinafter fully"described,illus- In describing my invention in detail, reference will be hadto the aceompanyingdr'awing wherein like characters denote" like or 'J corresponding plarts, throughout the several views,*and in w ich:

Fig. 2 is a plan view of the device illusfrom thel'eft side of Fig. 1; and Fig. 4 is a vertical axial section through the carryingwheel forming-a part of my in? vention, a fragmentary portion of themotor being shown in elevation.

trated in the accompanying drawing and'specifically'pointed out in the appended claims.

Figure 1"'is a side elevation of this im- --proved-gr1nd1ng device and mounting.

V duce a support for a grinding device adapted Referring to the drawing, lrepresentsthe driving element of this improved grinding device, which is preferably an electric motor,

provided with the usualshaft orspindle 2,,-

The ends of the arms the brackets let and 15 upon which a grinding wheel 3 is mounted in any desired manner. This grinding wheel may be of any desired material or construction and is to be selected to best suit the purpose for which it is to be used. The motor 1, shaft 2 and wheel 3 constitute a usual portable grinding unit;

For the purpose of supporting this grinding unit, a collar or inner ball race 4, F igure- 4, is fixedly mounted upon the barrel of the motor. This ball race is preferably formed with one or more grooves-5. Encompassin-g this ball race 4 is another collar or outer ball race 6 likewise formed with grooves7 equal in number to and aligned with the grooves 5. Interpos'ed between the races 4 and 6 and nested in the grooves and 7 are a plurality offballs 8 which are inserted through the plugged openings '9 as will stood. Theouter face of the outer race 6 is formed withfa concave periphery or seat 10 as will be apparent'from the drawing. Mounted in the concave periphery is arelatively soft annular member 11. This member is preferably made of an endless rubber tire of suitable hardness but may be made of any other suitable material, which has the. desired propertiesb For the purpose of guiding this grinding unit and controllingthe grinding I provide two handle members 12 and 13, whichfare suitablybent and are each securely fastened toone'of the brackets 14 and 15 on .the motor by means of-bolts lfi'and 1 7 respectively. It will be noted that the grips of the handle members arev parallel to the: axis of themotor. are eachformed. with a shoulder 18 at the point of attachment .to

movementofthe handles as will'be. understoo'd. One of the handles, 13,v is ref-v erably hollow so as to afford passage therethrough for wires 19 carrying currentto the motor. A suitable switch 20 is mounted on hand-le'18 in av convenient position for the operator to. start and stop. the motor...

The motor 1 is preferably astandard motor and the brackets 14: and 15 are two of the four feet with which standard motor frames are usually provided. The other two feet at the rear of the motor have been removed in the device shown on the drawing,although these feet might be left on without interfering with the operation of. the device in any The annular -member or ti-re *11: must be seft and yielding so. that it will not mark or scratch the surface which, in some case, has

.averyhigh degree of'polish and which would be irreparably damaged by a scratch. In addition it is important, especially in treating thin sheets of certain materials, such as stainless steel, for instance, that the material "ea-ofthis annular member l1 be yielding so be readily under- 7 so as to prevent angu-- .to the grinding action.

, a grinding wheel, this wheel may.

that it will distribute the loadover a rela 7 further present a friction surface tothe material so that the grinding unit will not skid or slide during the grinding operation.

This improved mounting for a grinding unit is especially adapted for removing pits, scratchesor other surface defects from relatively thin fiat'sheets or strips, either prior to, or subsequent to the .final finishing of such sheets. The drawing illustrates this improved mounting in operative relation to such a sheet of metal indicated at 21 In usingthis device the operator rests the tire 11 upon the plate 21 and starts the motor, holding the grinding unit by the grips on the handle member 12 and 13 and keeping the bottom of the wheel 3 somewhat above the plate. The operator then tilts the unit until the bottom of the periphery of the grinding wheel contacts the plate at the desired place. He then guides the grinding unit in the direction indicated by, the arrows in" Figure 2 which is preferably parallel to the grain of the material being ground'or finished, until the surface defect'lms been eliminated. It

will be noted that the construction ofthe mounting is such that it is relatively easy to feed the grinding unit parallel to the "plane of rotation of the grind'ing wheel. This is aided by the fact that the planeof the carrying wheel is fixed withrelation to the "axis of the grinding unit and is parallel to the "plane of the grinding wheeland that "therefore, the tendency ofthe carrying wheelis to move the grinding unitparalleltolitself. It should-also be noted that the motor and the handle members are rotatably mounted on' the supporting tirell and that there is therefore no tendency of the hand farthest from the operator to swing around horizontally as he reaches the end of the grinding stroke because the outer handle may be raised up w'a'rd'ly to compensate. for the stretching of the opera-tors arm. It will also be evident that theoperators control over the location,

amount andgual'ityaction will be much more A sensitive due to the fact that he need exert little or no physical effort to lift the weight of the motor and may direct" all of his energy This feature has the additional advantage that a larger and, more powerful motor may be used for grinding which has certain well known advantages. The fact that. the supporting tire 11 will not injure the surface and will not slip on the surface, also provides this unit with a stability which is work.

conducive to accurate grinding While the wheel 3 has been referred to as it is to be. understood that be. replaced by any wheel which may be used for similar operations,

' .finishing and removing of defects from thin metal, it will be understood that this device may be used with equal advantage in the strips or other shapes suitably mounted. on a fiat table or from relatively fiat surfaces of any kind.

\Vhile I have described the preferred embodiment of my invention, it must be understood that I do not limit myself to the specific construction therein shown, as various changes and modifications may be made in the construction of the mounting for the hand grinder without departing from. the

spirit of this invention or the scope of the appended claims: v

What I claim as new and desire to secure by Letters Patent is: V

1. In ahand grinding device, a power driven grinder unit comprising a grinder wheel and a motor, a carrier wheel encompassing said motor and adapted to support said'motor, and anti-friction means interposed between said carrier wheel and said motor.

2. In a handgrinding device, a motor con taining casing, an inner race member fixedly mounted therearound, an outer race member having a concave outer face, both sald races having registering opposite grooves, anti friction members in said grooves and a tire member seated 1n the concave face of said outer race member,

3. In a hand grinding device, a'motor containing casing, an inner race member fixedly mounted therearound, anouter race member having a concave outer face, both said races having registering opposite grooves, antifriction members in said grooves and a tire ,member seated in the concave face of said outer race member, grinding means associated with said motor, said tire and grinding means being parallel and axially aligned.

In testimony whereof, I have hereunto subscribed my name 1930. I V LOUIS SCHULTE.

this 21st day of August, 

